Gale Warning 100, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
500 AM AKST WED JAN 28 2009

.ANALYSIS AND UPPER LEVELS...

MASSIVE UPPER LEVEL RIDGE OVER THE GULF THIS MORNING WITH AN EQUALLY
LARGE TROUGH OVER THE BERING. ANOTHER TROUGH IS MOVING RAPIDLY ACROSS
NORTHERN AK. AT THE SURFACE...LOW PRESSURE COVERS THE EASTERN
ALEUTIANS AND AKPEN WITH A CENTER SOUTH OF DUTCH HARBOR. OTHERWISE
HIGH PRESSURE COVERS THE WESTERN BERING AND EASTERN RUSSIA...INTERIOR
AK...AND THE EASTERN GULF.

.MODEL DISCUSSION...

MODELS ARE IN EXCELLENT AGREEMENT WITH A PATTERN CHANGE OVER THE NEXT
SEVERAL DAYS. THIS WILL REPLACE THE GULF RIDGE WITH A LOW HEADED
TOWARD PRINCE WILLIAM SOUND...WITH AN ACCOMPANYING LONG DURATION SNOW
EVENT FOR AREAS SOUTH AND EAST OF THE AK RANGE. THE FORECAST LEANS
TOWARD THE GFS SOLUTION.

.SHORT TERM FORECAST...

IN THE WEST...THE WESTERN AND CENTRAL ALEUTIANS WILL RECEIVE SNOW
SHOWERS AS THE RIDGE BUILDS OVERHEAD THROUGH THU...AND THEN SNOW AS A
SERIES OF LOWS MOVES ALONG THE ISLANDS JUST SOUTH OF THE CHAIN
THROUGH FRI. THE EASTERN ALEUTIANS INITIALLY WILL BE IN THE WARM
SECTOR TODAY...BUT WILL THEN CHANGE TO SNOW WITH BLIZZARD CONDITIONS
THIS AFTERNOON AND TONIGHT BEFORE CHANGING TO SNOW SHOWERS THU INTO
FRI.

FOR SOUTHWEST AK...AS THE LOW MOVES FROM SOUTH OF DUTCH HARBOR TO
PRINCE WILLIAM SOUND...SIGNIFICANT SNOWFALL WILL AFFECT MOST OF THE
AREA THROUGH THU. DRY CONDITIONS WILL BE LIMITED TO THE KUSKOKWIM
DELTA. THU EVENING THROUGH FRI AFTERNOON A TROUGH DIGGING ACROSS NW
AK WILL MOVE TO THE AK RANGE WITH ANOTHER ROUND OF SNOW
SHOWERS...THIS TIME FOR ALL OF SOUTHWEST AK.

SOUTH AND EAST OF THE AK RANGE...THE LOW MOVING TO PWS WILL BRING
WITH IT A MOIST SOUTHWEST FLOW ALOFT WITH NO INDICATIONS OF
DOWNSLOPING. THIS MEANS PLENTY OF SNOW FOR INTERIOR AREAS BEGINNING
TODAY AND CONTINUING THROUGH FRI MORNING WEST OF THE TALKEETNAS...AND
INTO SAT FOR AREAS EAST OF THE TALKEETNAS. RAIN WILL MIX WITH SNOW
ALONG THE COAST WED NIGHT.

.LONG TERM FORECAST...

BERING SEA EFFECT SNOW SHOWERS WILL PERIST THROUGH THE WEEKEND. A
SECOND LOW WILL ARRIVE IN NEAR PWS SUN NIGHT...BRINGING ANOTHER ROUND
OF SNOW TO SOUTHWEST AK FOR THE WEEKEND....AND TO SOUTH CENTRAL ON
SUN.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...BLIZZARD WARNING 185
         BLIZZARD WATCH 181
MARINE...GALE 150 155 160 170 171
HEAVY FREEZING SPRAY 140 160 165 179
FIRE WEATHER...NONE

DS JAN 09